Centrifugal pump.



FERDINAND W. KROGH, OF SAN FRANCISCO, CALIFORNIA.

'CENTRIFUGAL BUMP.

Specification of Letters Patent.

Patented Oct. 4, 1910.

Application filed. November 28, 1905. Serial No. 289,486.

To all whom it may concern:

Be it known that I, FERDINAND W. KROGH, a citizen of the United States, residing in the city and county of San Francisco and State of California, have invented certain new and usefulImprovements in Centrifugal Pumps, of which the following is a speciT fication.

The object of my invention is to make the impelling wheel of a centrifugal pump float in the water or other liquid passing through the pump, andthereby relieve it from the frictlon ,which would otherwise develop between the wh'eel and the casing.

The invention consists in the eculiar arrangements and combinations 0 parts substantially as hereinafter described and particularly pointed out in the subjoined claims.

In the accompanying drawing I have shown in vertical section a pump containing my invention in what I conslder its best form. v

'- In the drawin'g:1 is the casing of the "pump. 2 is the im eller wheel revolving therein, and mounte on the shaft 3.v

4 4; is the inlet communicating with the suction openin 5, of the casin 6 is .the disc arge channel'o the casing, communicating with the dischar e'pipe 7.

8 is the ressure chamber w ich is arranged on t e side of theimpeller remote from the suction opening 5.

9 is the cylindricalhub of the impeller wheel 2. The hub 9 constitutes a plunger, and the chamber 8 its'cylinder.

'10 isa packin for the plunger, to reduce the leakage which would otherwise occur between it and the chamber..

11 is a pipe which connects the chamber 8 with both the discharge channel 6 and the suction 5.

12 is the branch connecting with the suction, and 13 the branch connecting with the discharge. These connections may be made with other parts of the apparatus, the only essentials bein that branch 12 shall draw liquid from c amber 8, while branch 13 conveys it thereto.

14 1s a valve in the branch 12.

'15 is a valve in the branch 13.

16 is a collar on shaft 3, provided with a groove 17. i

18 is a lever, fulcrumed on a convenient part of the casing, and en aging the groove 17. The outer end of the ever 1s connected by a rod. 19 with the handles of the valves 14; and 15. Interposed turnbuckles 20 and 21 serve for adjustment. Thus the valves are varied as to their opening, or closing, by the motion of shaft 3, and the adjustment is such that one valve will be opened as the other is closed, and vice versa. Also the collar 16 may be adjusted on the shaft.

The operation of the pump is this :Supposing the impeller wheel to'be running at sufiici'ent speed to produce a suction at 5 and a pressure at 6. If now the wheel is too low in the casing, the valve 14 will be closed and the valve 15 open, owing to the action on them of the lever 18, and Water under pressure will pass into chamber 8 under piston 9, and raise the wheel. If the wheel rise too high in the casing, the valve 14 will open and valve 15 close, and water will be released, or drawn from chamber 8, thus causing the wheel to descend. This alternate action will continue, until, at some point, an equilibrium is established, and the wheel will float free in the water, or other liquid.

In order that the suction through pipe 12 shall be efi'ective, it is advisable, to permit a leakage of liquid into the chamber 8. If

no packing were employed between the plunger and the walls of the chamber, there. would ordinarily be suflicient leakage around the plunger, especially after the pump had been in use for some time and the parts were worn. But I find a packing desirable to insure the accurate operation of the apparatus. Hence I provide a leakage passage 23, which I control by a valve-or plug 24. This passage is formed within the wall of the chamber and has its inlet and outlet respectively arranged on opposite sides of the rangeof movement of the inner end or portion 9 of the piston. Through it liquid under pressure is supplied to chamber 8 to balance the weight of the impeller shaft and the parts attached thereto.

Obviously structural variations may be the flow in said pipe, and means connected with the wheel for varying the openings of the valves. V

2. In a centrifugal pump, a casing, a chamber, an im el er having a piston in said chamber, Va ved ipes connecting said chamber with the suction opening and pressure portions of the casing, and lever 'connections between the valves of said pipes 10 and the impeller, adapted to open the valves alternately by predetermined variations in the position of the impeller from its condition of balance. I

In testimony whereof I have aflixed my signature in presence of subscribing wit- 5 nesses this 20th day of November 1905.

FERDINAND W. KROGH. v Witnesses:

I WM. S. BATES,

A. S. PARE'L 

